Anthropic's Claude Code CLI source code leaked onto GitHub recently. All of it. About 1,900 files and a lot of TypeScript.

I read through the key modules. What follows is a breakdown of the surprising parts: how the system actually works, where Anthropic made clever engineering choices, and where their approach diverges from OpenAI's Codex in ways you wouldn't guess from using either tool.

Here's what happens when you type a message into Claude Code:

A pattern for building personal knowledge bases using LLMs.

This is an idea file, it is designed to be copy pasted to your own LLM Agent (e.g. OpenAI Codex, Claude Code, OpenCode / Pi, or etc.). Its goal is to communicate the high level idea, but your agent will build out the specifics in collaboration with you.

Most people's experience with LLMs and documents looks like RAG: you upload a collection of files, the LLM retrieves relevant chunks at query time, and generates an answer. This works, but the LLM is rediscovering knowledge from scratch on every question. There's no accumulation. Ask a subtle question that requires synthesizing five documents, and the LLM has to find and piece together the relevant fragments every time. Nothing is built up. NotebookLM, ChatGPT file uploads, and most RAG systems work this way.

Follow the instructions below to deploy a Next.js app with a local PostgreSQL database to a VPS, secure it, and connect it to a custom domain with free SSL. Watch the accompanying tutorial on YouTube: https://www.youtube.com/watch?v=2T_Dx7YgBFw

1. Get your VPS server on Hostinger (Use code CODINGINFLOW for 10% off). Install Ubuntu 24 as the OS and set a root password.
2. Log into your server as root: ssh root@<your-server-ip>
3. Update Linux packages: apt update && apt upgrade -y
4. Create a new user: adduser